A multiplicity of flat faced or flush type tungsten carbide inserts positioned in the shirt-tail and the lower outer surfaces of the bit legs are currently being used in the industry to try to alleviate the erosion and abrasion of the bit legs. Because the hard inserts are flat faced and have no protrusion from the surface in which they are mounted, very little actual "back-reaming" of an undergage well bore or drilling up of the rock rubble in the annulus is accomplished. Some protection of the lower leg surfaces from severe abrasion is gained by using these inserts. Because they do no reaming, the flush type inserts in the lower leg surfaces do little to alleviate the in-thrust of the rotary cones, therefore bearing degradation remains a severe problem.